摘要:

The thermal conversion of propane to aromatics has been investigated by passing the gas through externally heated alloy steel tubes under conditions of turbulent flow. Recycling experiments carried out under pressure have shown that, when the gas flow is turbulent, high rates of conversion can be obtained at temperatures as low as 800–810 °C. Heat resistant chromium-nickel alloys of the 18:8 type have been found unsuitable for this purpose owing to the catalytic formation of carbon. Yields of 23.3 lb. of light oil per 1,000 cu. ft. of propane put through were obtained at 800 °C. together with 10 lb. of liquids boiling above 200 °C. The composition of the liquids obtained in these experiments has been determined by fractionation and chemical methods. The light oil obtained under the above conditions contains about 64% benzene, 14% toluene, 7.8% styrene and small amounts of cyclopentadiene, xylenes and higher aromatics. The liquids boiling above 200 °C. contain about 25% naphthalene and 12.5% anthracene together with smaller amounts of mono- and dimethyl naphthalenes, acenaphthene and phenanthrene.

ISSN:1923-4287    

DOI:10.1139/cjr34-012

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

The dried and ground corms lost 5% of their weight when extracted with petroleum ether, and a further 0.9% on subsequent extraction with methanol. Besides a trace of an essential oil, the methanol extract yielded water-soluble and water-insoluble portions. The former contained an acid, C5H8O5, m.p. 184 °C.;i-inositol, C6H6(OH)6, m.p. 224 °C.; a sugar forming phenylglucosazone; and a crystalline substance, (C6H10O6or C7H12O7), m.p. 120 °C., exhibiting the properties of a lactone. In the water-insoluble portion combined with the petroleum ether extract, the following substances have been found present: myricyl alcohol, C30H62O, m.p. 82–83 °C.; a new sterol, arisaesterol, C36H64O2, m.p. 135 °C.; phytosterolin, C31H52O6, m.p. 297 °C.; and a mixture of fatty acids.

ISSN:1923-4287    

DOI:10.1139/cjr34-013

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

The membranes synthesized by the action ofAcetobacter xylinuson fructose and on glycerol have been shown (after suitable purification) by the recognized methods of methylation, acetylation, acetolysis and hydrolysis to be chemically identical with cotton cellulose. These conclusions are confirmed by the results of X-ray analysis.The X-ray investigation by W. A. Sisson and G. L. Clark indicates the identity of the cellulose membranes formed from glucose, fructose, glycerol, sucrose, galactose and mannitol by the action ofAcetobacter xylinusand thus lends support to the view that the same polysaccharide is synthesized by the organism whenever cell-wall formation (growth) occurs and that this polysaccharide is chemically identical with cotton cellulose.

ISSN:1923-4287    

DOI:10.1139/cjr34-014

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

The rates of diffusion of sodium hydroxide, sodium chloride and hydrochloric acid into chips of black spruce heartwood impregnated with water were measured for different shapes of chip at 20, 50, and 75 °C. In the longitudinal direction of the wood, hydrochloric acid diffuses the most rapidly and sodium hydroxide and sodium chloride at nearly the same rates. In the lateral direction sodium hydroxide diffuses the most rapidly, owing to its action on the wood. Concentration of electrolyte is practically without influence on the time to half-value for sodium hydroxide and hydrochloric acid. The density of the wood does not affect the rate of diffusion of sodium hydroxide.The rate of diffusion of water into air dry chips was measured at 20 and 50 °C.

ISSN:1923-4287    

DOI:10.1139/cjr34-015

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

There are several possible causes of the absence or low frequency of many chromosomal and genetic types in crosses between 42- and 28-chromosome species of wheat. The actual effects of these possible causes are:1. Pre-gametic causes — effect small. Among pollen grains which develop normally all chromosomal types are found but not quite in theoretical proportions; those with chromosome numbers intermediate between the 14 and 21 of the parents are somewhat deficient. Intermediate numbers are more abundant among retarded grains.2. Gametic(a) Male(1) Outright abortion of pollen grains — 5 to 10%.(2) Retardation of development — 25 to 30%.(3) Failure of pollen germination — the above 25 or 35%, plus probably as much more.(4) Competition and selective fertilization — impossible to determine accurately but probably some effect.(b) Female — very little. Apparently nearly all female gametes are capable of functioning but 50% usually remain unfertilized.3. Endospermic — abortion and abnormal development cause important effects particularly in relation to female gametes but they cannot be separated completely from possible direct embryonic effects.4. Embryonic — about half the embryos abort before the seed is ripe and at least half theF2seeds usually fail to germinate. These are in part and may be wholly endospermic effects.The gametic and endospermic influences are such as to reduce the proportion of plants with chromosome combinations intermediate between those of the parents.

ISSN:1923-4287    

DOI:10.1139/cjr34-016

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

This paper deals principally with the classification of the bees of the generaHalictusandAndrenacollected during a five-year project on the pollination of the apple in the Annapolis-Cornwallis Valley, Nova Scotia. Keys for the separation of the species concerned are given, together with figures of the eighth and ninth abdominal sterna of the males, which were found very useful in separating related species. One new species,Andrena kalmiaeAtwood, and the true male ofA.ceanothiVier., are described, and a re-description ofHalictus arcuatusRob. is given, including a summer form which is presumably sterile. The taxonomic section is prefaced by brief notes on economic importance and biology of the genera.

ISSN:1923-4287    

DOI:10.1139/cjr34-017

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

An apparatus is described whereby the experimental drying of alimentary pastes may be conducted automatically under a pre-determined program of temperature, time and humidity relations.The air employed for drying is continuously recirculated, dehumidification being obtained by by-passing an increasing proportion over refrigerating coils through the medium of an especially designed valve, operated electromagnetically and timed by an electric clock.Complete control of the time-humidity relation is obtained by a regulated steam input from a water resistance boiler controlled by the action of the wet bulb recording pen in conjunction with a conducting strip placed on the recorder chart.While specifically designed for drying alimentary pastes, the apparatus should be well adapted to other classes of drying studies and may also be employed to maintain constant conditions of temperature and humidity.

ISSN:1923-4287    

DOI:10.1139/cjr34-018

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

The standard precipitin ring test was applied in an effort to differentiate the following smut fungi: (1) monosporidial cultures ofSorosporium reilianum(Kühn) McAlp.,Ustilago hordei(Pers.) K. & S.,Ustilago levis(K. & S.) Magn.,Ustilago zeae(Beck.) Ung., and (2) mass cultures ofUstilago hypodites(Schlecht.) Fr.,Ustilago tritici(Pers.) Rost.,Ustilago avenae(Pers.) Jens.,Ustilago levis(K. & S.) Magn., andUstilago zeae(Beck.) Ung. The results obtained indicate that monosporidial strains could be satisfactorily differentiated. Although they were frequently mutually reactive in undiluted serum-antigen mixtures, their specificity was apparent in the persistence of the precipitin ring at greater dilutions with homologous than with heterologous mixtures. Mass cultures were not so satisfactorily differentiated and showed many cross reactions. The results indicate that closely related species and physiological forms of fungi are not easily differentiated since characters common to two or more of them apparently tend to mask their ultimate differences. The method, however, offers possibilities as regards the more intimate affinities among groups of doubtful species or genera.

ISSN:1923-4287    

DOI:10.1139/cjr34-019

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

For map plotting purposes it is essential to know the principal distance (focal length) of air cameras, preferably for rays making various angles with the lens axis. A compact apparatus has been developed for making the necessary measurements and has been used for investigating the lens distortion in a number of air cameras. This method of finding distortion has the advantage that it takes into account the effect of the glass plate fitted in film cameras to maintain the film flat during exposure.The distortion is given as the linear displacement in the plane of the photograph. It is felt that in this form the results are of more interest to those using air photographs. By simple calculations the figures can be changed to give the distortion in the forms more usual in the treatment of lens design.

ISSN:1923-4287    

DOI:10.1139/cjr34-020

出版商:NRC Research Press    

年代:1934

数据来源: NRC

摘要:

Accurate formulas are presented showing the power radiated by a stretched circular membrane vibrating with small amplitudes and an arbitrary number of nodal circles or diameters. When the nodes are circular, the sound emitted is expressed as a sum of the products of simple functions ofka,J0(2ka),J1(2ka) by the definite integral ofy2s/(κ2a2/k2a2 − 1 + y2)2taken between the limits zero and unity. For values ofka = 2πa/λ between zero and two, where the radiusais taken as 10 cm., the membrane vibrating in its fundamental mode emits between three and four times as much power as the piston having the same maximum velocity at its centre. The first and second overtones have about the same strength as the corresponding fundamental frequencies, so the power radiated increases less rapidly with frequency than when nodes are absent.

ISSN:1923-4287    

DOI:10.1139/cjr34-021

出版商:NRC Research Press    

年代:1934

数据来源: NRC